Pneumatic jack structure of various types have been employed in the prior art as exemplified by the U.S. Pat. Nos. 4,542,882; 5,121,900; 5,184,930; 3,993,286; and 5,232,206.
The jack structure of the prior art has heretofore been of a relatively complex structure as in the manner of U.S. Pat. No. 4,542,882 a bag arranged to receive pressurized air from an exhaust system into a single flexible bag structure.